Method for manufacturing an aluminium alloy automobile hub

ABSTRACT

Provided is a method for manufacturing an aluminium alloy automobile hub, the method comprising the following steps: putting a workpiece in the shape of a shallow hat on a first spinning base, wherein an opening of the workpiece faces upward, and a first upper pressure head extends into the workpiece from above and then fixes the workpiece; and pressing out a rim for spokes on an outer side of a lower portion of the workpiece by means of spinning rollers. In the method, series and improved aluminium alloy sheets are taken as raw materials and are integrally formed by multi-pass powerful spinning machining, such that same are deformed step by step in the whole process according to the properties of aluminium alloy, thereby forming a blank of the hub, and then the hub is formed by finishing.

FIELD

The present disclosure relates to a manufacturing method in the field of hub production technologies, and more particularly, to a method of manufacturing an aluminium alloy automobile hub.

BACKGROUND

There are currently two methods of manufacturing a hub, including production modes of casting and forging. It is easy to cause slag inclusion and air hole, subsurface porosity, air pocket, shrinkage blowhole, pinhole and other quality defects in casting, the quality detection equipment designed for treating these quality defects are various and complicated, and it is low in the product strength, large in the equipment investment, high in the energy consumption, and severe in the environment pollution. Ordinary 6061 alloy aluminum bar is used domestically as the material of the forging stock in the production mode of forging, which increases the strength of the product, but still has the problem of deformation and air leakage, and the manufacturing cost is high, and it is to the disadvantage of popularization. In addition, under the two production modes above, the two modes of spin-casting (i.e., casting+spinning) and spin-forging (i.e., forging+spinning) are extended, but the existing technical deficiency is still not basically solved. Therefore, we provide a method for manufacturing an aluminium alloy automobile hub to solve the problems above.

SUMMARY

An object of the present disclosure lies in providing a method for manufacturing an aluminium alloy automobile hub, which can reduce the difficulty and cost of manufacturing an aluminum hub.

The solution of the present disclosure to solve the technical problem is a method for manufacturing an aluminium alloy automobile hub, which comprises the following steps of:

1) putting a workpiece in a shape of a shallow hat on a first spinning base, wherein an opening of the workpiece faces upward, and a first upper pressure head extends into the workpiece from above and then fixes the workpiece; and

2) pressing out a rim for spokes on an outer side of a lower portion of the workpiece by means of spinning rollers.

As further improvement to the technical solution above, further comprising, after step 2), sleeving the workpiece onto a second spinning base with the opening of the workpiece downward, wherein the workpiece is fixed to the second spinning base by a second upper pressure head, with a side wall of the workpiece being thinned by spinning through the spinning rollers to finally form a hub blank by spinning.

As further improvement to the technical solution above, further comprising heat treatment and repair treatment to the hub blank, which comprises the following steps of:

a) conducting T6 solution and aging treatments, wherein the solution treatment, which is conducted at a temperature of 530-540° C. for 150-180 min, comprises placing the hub blank into a cold water tank within 25 s and stirring the cold water until the temperature of the hub blank is cooled to water temperature; and wherein the aging treatment comprises placing the hub blank into an aging oven with an aging temperature of 150-170° C. for 12-15 h, and then slowly cooling the hub blank to room temperature with the oven; and

b) conducting reconstructive repair to the hub blank by a special tool after the hub blank is slightly deformed by the solution and aging treatments, so as to comply with next machining requirement on the hub.

As further improvement to the technical solution above, further comprising, machining the hub blank after reconstructive repair in a lathe and a processing center to finally manufacture the hub.

As further improvement to the technical solution above, further comprising, before step 1), selecting an aluminum alloy disk with a corresponding thickness and diameter, locating and punching the aluminum alloy disk, and spinning the aluminum alloy disk spun into the workpiece in a shape of a shallow hat by strong spinning.

As further improvement to the technical solution above, the first spinning base is provided at a middle thereof with a locating chamber and a locating pin in the middle of the locating chamber, the locating chamber is provided with a circle of cambered moulding surface at an upper portion of a side wall of the locating chamber, and the cambered moulding surface is located outside the side wall of the locating chamber.

The present disclosure has the beneficial effects that: 6-series and improved aluminum alloy sheets are taken as raw materials in the present disclosure and integratedly formed by multi-pass powerful spinning machining. The hub, as a whole, is free of weld joints, has high strength, stable quality and light weight, and is applicable to electric buses, trucks, cars, electric cars, etc. The hidden quality problems in casting an aluminium hub are solved, the material stability of the forged aluminium hub is ensured, the investment cost is low, and there is no pollution. Specifically the beneficial effects are as follows.

1. small amount of investment: since the main processing equipments are spinning machine, lathe and other standard equipments without heavy industry equipment, the investment is low;

2. no pollution: since a spinning cold machining is the main production process, a smelting furnace used in casting and a heating furnace used in forging are eliminated, which reduces the energy consumption and has no pollution.

3. the production process is simplified, which facilitates to realize the high-degree automation of a production line, so that the manufacture of the hub is converted into light industry and low difficulty from heavy industry and high difficulty, and the direct effect is to greatly reduce the cost of the hub; and

4. little rim charge is generated in production, which reduces the energy consumption.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to describe the technical solution in the embodiments more clearly, the drawings used in the detailed description are simply described hereinafter. Apparently, the described drawings are only representative embodiments of the present disclosure instead of all embodiments, and other design schemes and drawings can be obtained according to these drawings by those skilled in the art without any creative works.

FIG. 1 is a structural schematic diagram of a workpiece in the present disclosure;

FIG. 2 is a structural schematic diagram when a rim for spokes is spun in the present disclosure;

FIG. 3 is a schematic diagram of the workpiece with the rim in the present disclosure;

FIG. 4 is a structural schematic diagram of a hub blank in the present disclosure;

FIG. 5 is a top view of the hub in the present disclosure; and

FIG. 6 is a side view of the hub in the present disclosure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The conception, specific structure and the generated technical effect of the present disclosure are clearly and completely described with reference to the embodiments and the drawings to fully understand the object, solution and effect of the present disclosure. Apparently, the described embodiments are only representative embodiments of the present disclosure instead of all embodiments, and based on the embodiments of the present disclosure, other embodiments obtained by those skilled in the art without any creative works all fall within the protection scope of the present disclosure. In addition, all coupling/connection relations referred to herein indicate preferable connection relation formed through adding or reducing a connection accessory instead of singly indicating the direct connection of the components.

With reference to FIG. 1 to FIG. 6, a method for manufacturing an aluminium alloy automobile hub comprises the following steps of:

1) putting a workpiece 1 in a shape of a shallow hat on a first spinning base 3, wherein an opening of the workpiece 1 faces upward, and a first upper pressure head 2 extends into the workpiece 1 from above and then fixes the workpiece 1, and the first upper pressure head is also a mould, which belongs to an internal model and used for fixing partial shape of the spoke inside the workpiece; and

2) pressing out a rim for spokes on an outer side of a lower portion of the workpiece 1 by means of spinning rollers 5.

In the production process, the materials outside the workpiece 1 are squeezed through the spinning rollers 5, so that after the materials are issued to lower levels, the rim 6 for spokes is formed under the mutual effect of the first spinning base 3 and the spinning rollers 5.

As a preferred embodiment, further comprising, after step 2), sleeving the workpiece 1 onto a second spinning base with the opening of the workpiece 1 downward, wherein the workpiece 1 is fixed to the second spinning base by a second upper pressure head, with a side wall of the workpiece 1 being thinned by spinning through the spinning rollers 5 to finally form a hub blank by spinning. At the moment, strong spinning is used, which is generally divided into a cold spinning and a heat spinning. In the process, the cold spinning and the heat spinning can both be implemented. The second spinning base is a mould formed by a rim, and is also called an internal model, and the spinning rollers are molded against the internal model by pressing the side wall of the workpiece or the rim.

As a preferred embodiment, further comprising heat treatment and repair treatment to the hub blank, which comprises the following steps of:

a) conducting T6 solution and aging treatments, wherein the solution treatment, which is conducted at a temperature of 530-540° C. for 150-180 min, comprises placing the hub blank into a cold water tank within 25 s and stirring the cold water until the temperature of the hub blank is cooled to water temperature; and wherein the aging treatment comprises placing the hub blank into an aging oven with an aging temperature of 150-170° C. for 12-15 h, and then slowly cooling the hub blank to indoor temperature with the oven; and

b) conducting reconstructive repair to the hub blank by a special tool after the hub blank is slightly deformed by the solution and aging treatments, so as to comply with next machining requirement on the hub.

As a preferred embodiment, further comprising, machining the hub blank after reconstructive repair in a lathe and a processing center to finally manufacture the hub.

As a preferred embodiment, further comprising, before step 1), selecting an aluminum alloy disk with a corresponding thickness and diameter, locating and punching the aluminum alloy disk, and spinning the aluminum alloy disk spun into the workpiece 1 in a shape of a shallow hat by strong spinning. After the spinning is ended, the workpiece 1 in a shape of a shallow hat is put on the mould with the opening thereof downward.

Further, as a preferred embodiment, the first spinning base 3 is provided at a middle thereof with a locating chamber and a locating pin in the middle of the locating chamber, the locating chamber is provided with a circle of cambered moulding surface 4 at an upper portion of a side wall of the locating chamber, and the cambered moulding surface 4 is located outside the side wall of the locating chamber. In the production process, the materials outside the workpiece 1 are squeezed through the spinning rollers 5, so that after the materials are issued to lower levels, the rim 6 for spokes is formed under the mutual effect of the first spinning base 4 and the spinning rollers 5.

A preferred embodiment of the present disclosure is as follows.

Step 1: selecting materials. An aluminum alloy disk with a corresponding thickness and diameter is determined to be purchased according to the specification of the hub to be manufactured, and the 6-series and improved aluminum alloy sheets are used in the aluminum alloy disk.

Step 2: locating and punching. The aluminum alloy disk in step 1 is located and punched through a punching machine, so as to determine a central point of spinning.

Step 3: initial spinning. The spinning mould is prepared according to the specification and shape of the hub to be manufactured, and the aluminum alloy disk is firstly spun into the workpiece 1 in a shape of a shallow hat by strong spinning to form the shape as shown in FIG. 1.

Step 4: reverse spinning. Opening an external mold, wherein the workpiece 1 in a shape of a shallow hat is installed in the spinning machine with an opening of the workpiece upward, the workpiece 1 is pressed by the first upper pressure head 2 in spinning, the spinning rollers 5 spin the workpiece 1 from top to bottom, and as shown in FIG. 2, the aluminum material of the workpiece 1 after strong spinning is spun to the rim 6 for spokes to form the shape as shown in FIG. 3.

Step 5: fine spinning. After the opening of the workpiece 1 is arranged downwardly, the workpiece 1 is sleeved onto the second spinning base, the workpiece 1 is fixed on the second spinning base by the second upper pressure head, and the external wall of the workpiece 1 is spun to be thinner and in a shape through the mould by strong spinning, so as to form the hub blank in the shape as shown in FIG. 4.

The reason of using multi-passes spinning as steps 3 to 5 is that one-pass spinning has limited deformation due to the aluminum sheet having relatively large thickness, especially the reverse spinning is further required. The thickness of the material is increased to the rim 6 of the spoke while the workpiece 1 becomes thinner. The spinning forming process is then performed on the workpiece 1, wherein the material is gradually deformed in the whole process according to the performance of the aluminum alloy to finally form the hub blank. The higher accuracy the spinning machine and the mould have, the closer the hub blank is to the finished product, the less the working allowance is, and the lower the cost is.

Step 6: solution and aging treatments. After the hub blank in step 5 is spun and formed, T6 solution and aging treatments needs to be conducted, wherein the solution temperature is 530-540° C. and the solution time is 150-180 min; the hub blank is placed into a cold water tank within 25 s, and the cold water is stirred, until the temperature of the hub blank is cooled to the water temperature.

And then conducting aging treatment. The hub blank is placed in an aging oven, wherein the aging temperature is 150-170° C. and the aging time is 12-15 h, and then the hub blank is slowly cooled to the indoor temperature with the oven.

Step 7: repairing. Reconstructive repair is conducted to the hub blank by a special tool after the hub blank is slightly deformed by the solution and aging treatments, so as to comply with next machining requirement on the hub.

Step 8: machining. The hub blank after reconstructive repair is machined in a lathe and a processing center using a special clamp, to finally manufacture the hub product as shown in FIG. 5 and FIG. 6.

The contents above specifically describe the preferred embodiments of the present disclosure, but the present disclosure is not limited to the embodiments, those skilled in the art can make various equal deformations or replacements without departing from the spirit of the present disclosure, and these equal deformations or replacements shall all fall within the scope limited by the claims of the application. 

1. A method for manufacturing an aluminium alloy automobile hub, the method comprising the following steps: 1) putting a workpiece in a shape of a shallow hat on a first spinning base, wherein an opening of the workpiece faces upward, and a first upper pressure head extends into the workpiece from above and then fixes the workpiece; and 2) pressing out a rim for spokes on an outer side of a lower portion of the workpiece by means of spinning rollers.
 2. The method for manufacturing an aluminium alloy automobile hub according to claim 1, further comprising, after step 2), sleeving the workpiece onto a second spinning base with the opening of the workpiece downward, wherein the workpiece is fixed to the second spinning base by a second upper pressure head, with a side wall of the workpiece being thinned by spinning through the spinning rollers to finally form a hub blank by spinning.
 3. The method for manufacturing an aluminium alloy automobile hub according to claim 2, further comprising heat treatment and repair treatment to the hub blank, which comprises the following steps of: a) conducting T6 solution and aging treatments, wherein the solution treatment, which is conducted at a temperature of 530-540° C. for 150-180 min, comprises placing the hub blank into a cold water tank within 25 s and stirring the cold water until the temperature of the hub blank is cooled to water temperature; and wherein the aging treatment comprises placing the hub blank into an aging oven with an aging temperature of 150-170° C. for 12-15 h, and then slowly cooling the hub blank to indoor temperature with the oven; and b) conducting reconstructive repair to the hub blank by a special tool after the hub blank is slightly deformed by the solution and aging treatments, so as to comply with next machining requirement on the hub.
 4. The method for manufacturing an aluminium alloy automobile hub according to claim 3, further comprising, machining the hub blank after reconstructive repair in a lathe and a processing center to finally manufacture the hub.
 5. The method for manufacturing an aluminium alloy automobile hub according to claim 1, further comprising, before step 1), selecting an aluminum alloy disk with a corresponding thickness and diameter, locating and punching the aluminum alloy disk, and spinning the aluminum alloy disk spun into the workpiece in a shape of a shallow hat by strong spinning.
 6. The method for manufacturing an aluminium alloy automobile hub according to claim 1, wherein the first spinning base is provided at a middle thereof with a locating chamber and a locating pin in the middle of the locating chamber, the locating chamber is provided with a circle of cambered moulding surface at an upper portion of a side wall of the locating chamber, and the cambered moulding surface is located outside the side wall of the locating chamber. 